c64b94bd1 p2p: fix endianness when checking IPv6 addresses mapping to IPv4 (moneromooo-monero)
67f2bec2d p2p: make this work with boost <= 1.65 (pffff) (moneromooo-monero)
ffdf1fb1d p2p: rewrite boost's make_address_v4 to cater for < 1.66 (moneromooo)
IPv6 addresses include a range that can map IPv4 addresses,
which allowed those mapped addresses to bypass filtering.
This filter should be replaced by AS filtering at some point.
When a handshake fails, it can fail due to timeout or destroyed
connection, in which case the connection will be, or already is,
closed, and we don't want to do it twice.
Additionally, when closing a connection directly from the top
level code, ensure the connection is gone from the m_connects
list so it won't be used again.
AFAICT this is now clean in netstat, /proc/PID/fd and print_cn.
This fixes a noisy (but harmless) exception.
- New flag in NOTIFY_NEW_TRANSACTION to indicate stem mode
- Stem loops detected in tx_pool.cpp
- Embargo timeout for a blackhole attack during stem phase
4771a7ae p2p: remove obsolete local time in handshake (moneromooo-monero)
2fbbc4a2 p2p: avoid sending the same peer list over and over (moneromooo-monero)
3004835b epee: remove backward compatible endian specific address serialization (moneromooo-monero)
39a343d7 p2p: remove backward compatible peer list (moneromooo-monero)
60631802 p2p: simplify last_seen serialization now we have optional stores (moneromooo-monero)
9467b2e4 cryptonote_protocol: omit top 64 bits of difficulty when 0 (moneromooo-monero)
b595583f serialization: do not write optional fields with default value (moneromooo-monero)
5f98b46d p2p: remove obsolete local time from TIMED_SYNC (moneromooo-monero)
During the handshake for an incoming connection, the peer id is checked against the local node's peer id only for the specific zone of the incoming peer, in order to avoid linking public addresses to tor addresses:
5d7ae2d279/src/p2p/net_node.inl (L2343)
However, on handshakes for outgoing connections, all zones are checked:
5d7ae2d279/src/p2p/net_node.inl (L1064)
If an attacker wanted to link a specific tor node to a public node, they could potentially connect to as many public nodes as possible, get themselves added to the peer whitelist, maybe stuff some more attacker-owned addresses into the greylist, then disconnect, and for any future incoming connections, respond with the tor node's id in an attempt to link the public/tor addresses.
Nodes remember which connections have been sent which peer addresses
and won't send it again. This causes more addresses to be sent as
the connection lifetime grows, since there is no duplication anymore,
which increases the diffusion speed of peer addresses. The whole
white list is now considered for sending, not just the most recent
seen peers. This further hardens against topology discovery, though
it will more readily send peers that have been last seen earlier
than it otherwise would. While this does save a fair amount of net
bandwidth, it makes heavy use of std::set lookups, which does bring
network_address::less up the profile, though not too aggressively.